An unprecedented pro-Israel television advertising campaign with roots in Silicon Valley began running Monday in 100 major markets around the country, the first time that American Jewish groups have turned to the airwaves to promote Israel.

The ads are designed to counter what organizers see as biased news coverage of the conflict in the Middle East, and they come at a time when public support for Israel’s actions has been waning.

“We decided to fill the niche of informing people about the Israel that exists beyond the conflict,” said Larry Weinberg, executive vice president of Israel21c, a Cupertino non-profit group started by local entrepreneurs. Israel21c and the New York-based American Jewish Committee are co-sponsoring the $1 million ad campaign, which started in New York, Washington and Silicon Valley in mid-September.

The ads are running from morning through prime time on CNBC, MSNBC, Fox News, CNN and CNN’s Headline News.

The 30-second ads depict a peaceful Israel, in stark contrast to the images of carnage often reflected on the nightly news. They show modern high-rises, an Arab woman voting, people of various faiths praying, and scenes from an office and a college campus.

“Israel is the only democracy in the Middle East today, America’s ally,” begins one of two ads. News coverage of the Middle East has distorted Israel’s image in the United States, implying “moral equivalence” between Palestinian suicide bombers and the Israeli response, said Jennifer Laszlo Mizrahi, a Washington consultant who helped produce the ads.

Polling by a bipartisan group of consultants involved in the ad campaign found that American public support of Israel in the current conflict has dropped from 60 percent to 42 percent. Support for Palestinians has fallen as well, from 10 percent to 8 percent.

Some Palestinian-Americans criticized the ads as misleading and subtly racist.

“The message is, ‘We’re like you, Americans, and the Arabs aren’t. They’re the forces of the desert,’ ” said James Zogby, founder and president of the Arab American Institute in Washington. “The irony, of course,” Zogby said, is that it is Israel’s “occupation that denies Palestinians the very values and goals that Israel cherishes for itself.”

Weinberg said Israel isn’t a “perfect democracy,” but said if the ads create an “us and them” mentality on political grounds, they have succeeded. “There are multiethnic, democratic states that provide their citizens with rights, and those that don’t,” he said.

American Jewish groups have often run pro-Israel print ads in newspapers but haven’t turned to television. Weinberg said that the Jewish community has avoided the airwaves for fear of tapping into stereotypes of “Jews controlling the media,” but that the ads are testing well. The campaign hit one obstacle when CNN refused to provide airtime, saying it doesn’t take “international advocacy ads that involve regions in conflict.”

CNN spokesman Matthew Furman said the network also has turned down promotional ads from Saudi Arabia and other Arab nations recently.

Israel21c was able to place the ads on CNN by going through local cable affiliates.